Array::fill() and array::swap() in C++ STL?

In this section we will see what are the usage of array::fill() and the array::swap() in C++ STL.

The array::fill() function is used to fill the array with some specified value. Let us see one example to get the idea.

Example

 Live Demo

#include<iostream>
#include<array>
using namespace std;
main() {
   array<int, 10> arr = {00, 11, 22, 33, 44, 55, 66, 77, 88, 99};
   cout << "Array elements: ";
   for(auto it = arr.begin(); it != arr.end(); it++){
      cout << *it << " ";
   }
   //fill array with 5
   arr.fill(5);
   cout << "\nArray elements after fill: ";
   for(auto it = arr.begin(); it != arr.end(); it++){
      cout << *it << " ";
   }
}

Output

Array elements: 0 11 22 33 44 55 66 77 88 99
Array elements after fill: 5 5 5 5 5 5 5 5 5 5

The array::swap() function is used to swap the contents of one array to the other array. Let us see one example to get the idea.

Example

 Live Demo

#include<iostream>
#include<array>
using namespace std;
main() {
   array<int, 10> arr1 = {00, 11, 22, 33, 44, 55, 66, 77, 88, 99};
   array<int, 10> arr2 = {85, 41, 23, 65, 74, 02, 51, 74, 98, 22};
   cout << "Array1 elements: ";
   for(auto it = arr1.begin(); it != arr1.end(); it++){
      cout << *it << " ";
   }
   cout << "\nArray2 elements: ";
   for(auto it = arr2.begin(); it != arr2.end(); it++){
      cout << *it << " ";
   }
   //swap array elements
   arr1.swap(arr2);
   cout << "\nArray1 elements (After swap): ";
   for(auto it = arr1.begin(); it != arr1.end(); it++){
      cout << *it << " ";
   }
   cout << "\nArray2 elements (After swap): ";
   for(auto it = arr2.begin(); it != arr2.end(); it++){
      cout << *it << " ";
   }
}

Output

Array1 elements: 0 11 22 33 44 55 66 77 88 99
Array2 elements: 85 41 23 65 74 2 51 74 98 22
Array1 elements (After swap): 85 41 23 65 74 2 51 74 98 22
Array2 elements (After swap): 0 11 22 33 44 55 66 77 88 99